Síntese e avaliação da atividade fitotóxica de novos análogos oxigenados do ácido helmintospórico

AUTOR(ES)

Barbosa, Luiz Cláudio de Almeida, Demuner, Antônio Jacinto, Maltha, Célia Regina Álvares, Silva, Patrícia Silvana da, Silva, Antônio Alberto da

FONTE

Química Nova

DATA DE PUBLICAÇÃO

2003-10

RESUMO

Several compounds related to helminthosporic acid (3) were synthesized via the [3+4] cycloaddition. The reaction of 3-hydroxymethyl-2-methylfuran (12) with 1,1,3,3-tetrabromo-4-methylpentan-2-one (13) resulted in 7-hydroxymethyl-4alpha-isopropyl-1alpha-methyl-8-oxabicyclo[3.2.1]oct-6-en-3-one (8) (37%) and 7-hydroxymethyl-2alpha-isopropyl-1alpha-methyl-8-oxabicyclo[3.2.1]oct-6-en-3-one (14) (12%), which were converted into 7-formyl-4alpha-isopropyl-1alpha-methyl-8-oxabicyclo[3.2.1]oct-6-en-3-one (16) (32% from 8) and 7-formyl-2alpha-isopropyl-1alpha-methyl-8-oxabicyclo[3.2.1]oct-6-en-3-one (18) (40% from 14), respectively. Reduction of (8) resulted in 7-hydroxymethyl-4alpha-isopropyl-1alpha-methyl-8-oxabicyclo[3.2.1]oct-6 -en-3alpha-ol (11) (63% from 8) and 7-hydroxymethyl-4alpha-isopropyl-1alpha-methyl-8-oxabicyclo[3.2.1]oct-6-en-3 beta-ol (15) (30% from 8). The 4alpha-isopropyl-1alpha-methyl-3-oxo-8-oxabicyclo[3.2.1]oct-6-en-7-oic acid (19) was obtained by oxidation of (16) (78%). The results of biological tests are described in details. The best result was observed for compound (15) that caused 76% inhibition on the root growth of D. tortuosum.

Documentos Relacionados

• Síntese e avaliação da atividade fitotóxica de novos oxabiciclos análogos ao ácido helmintospórico
• Síntese e avaliação da atividade fitotóxica de análogos ao alternariol
• Síntese e avaliação da atividade fitotóxica de derivados da α-Santonina
• Síntese e avaliação da atividade fitotóxica de compostos heteroaromáticos análogos aos nostoclídeos
• Estudos para a síntese da viscosamina, de análogos oxigenados e de novos sais de piridínio quirais usando a reação de zincke